apixaban for extended anticoagulation (apidulcis)

Conditions: Venous Thromboembolism; Anticoagulants

Summary: the study aims at optimizing the long-term and extended management of patients with a first episode of venous thromboembolism (proximal deep vein thrombosis with or without pulmonary embolism) (vte). patients at high risk of recurrence (with altered d-dimer test), who had received anticoagulation (whatever the drug used) for 12-15 months after the first episode of thrombosis, will be treated with apixaban 2,5 mg x 2 for 18 months as extended treatment. patients at low risk, with normal d-dimer test, will stop anticoagulation definitely.

this prospective cohort study aims to assess the efficacy and safety of a management procedure to decide on giving or not an extended anticoagulation (administering apixaban 2 2.5 mg twice daily ) to outpatients with a single episode of proximal deep vein thrombosis of the lower limbs and/or pulmonary embolism who had received 12-15 months of anticoagulation (whatever the anticoagulant drug used). the study seeks to assess whether a management procedure involving d-dimer testing assessment can identify a subset of subjects at low risk of recurrence in whom an extended anticoagulation can be safely avoided.

Eligibility criteria:
inclusion criteria: * first unprovoked venous thromboembolic event * venous thromboembolic events associated with one or more risk factors that are no longer present * age older than 18 or younger than 75 years * capacity to give written informed consent exclusion criteria: * a) exclusion criteria regarding the index event * events usually associated with low risk of recurrence * deep vein thrombosis/ pulmonary embolism occurred within 3 months from major surgery or major trauma * isolated distal deep vein thrombosis (thrombosis of calf veins) * events associated with a very high risk of recurrence or occurrence of life-threatening recurrent events * pulmonary embolism episode with shock or life-threatening * isolated pulmonary embolism with a systolic pulmonary artery pressure \> 60 mmhg at presentation * deep vein thrombosis/ pulmonary embolism associated with active cancer, antiphospholipid syndrome or long-standing medical illnesses * more than one idiopathic event * index venous thromboembolic event in different sites than deep veins of the lower limbs or pulmonary arteries b) exclusion criteria present at the moment of patients' screening: * age younger than 18 or older than 75 years * more documented unprovoked venous thromboembolic episodes * pregnancy or puerperium * severe post-thrombotic syndrome (≥ 15 points at the villalta score) * solid neoplasia or blood disease in active phase or requiring chemotherapy/radiotherapy * all the clinical conditions requiring prolonged treatment with low molecular weight heparin * presence of overt, active chronic diseases (i.e. inflammatory bowel disease) * known serious thrombophilic alterations: * deficiencies of natural anticoagulants (antithrombin, protein c, protein s) * homozygosity for factor v leiden or factor ii g20210a mutations * double heterozygosity * presence of antiphospholipid syndrome * presence of vein cava filter * concomitant conditions (such as atrial fibrillation) requiring indefinite anticoagulation * severe cardio-respiratory insufficiency (nyha 3 or 4) * any absolute contraindications to anticoagulation treatment * any other contraindications to apixaban as per local smpc * life expectancy shorter than 1 year * refuse interruption of anticoagulation to perform serial d-dimer assessment * geographically inaccessible location * inability or refusal to give consent

Keywords: venous thromboembolism d-dimer apixaban extended treatment